Purple Sweet Potato Cake
An Original Recipe by Lorraine Elliott
Preparation time: 30 minutes
Cooking time: 1 hour
- 250g/8.8ozs butter, softened
- 1 cup caster or superfine sugar (use 1.5 cups if you like your cakes very sweet but I found 1 cup plenty)
- 4 eggs, at room temperature
- 2 teaspoons vanilla extract
- Purple food colouring (optional)
- 3 cups cake flour (see below)
- 2 teaspoons baking powder
- 1/2 teaspoon bicarbonate of soda
- 2 cups steamed ube or purple sweet potato, cooled
- 1 cup oil (flavourless one like canola, do not use olive oil)
-
300ml/10.flozs. coconut Milk
-
50g/1.7ozs. white chocolate
- 50gml/1.7flozs cream
- A few drops white on white colour (optional)
- Blackberries and purple flowers to decorate
To make cake flour, for every cup of plain flour, replace 2 tablespoons with cornflour or fine cornstarch
Ube can be purchased at large markets, especially ones that cater to Filipino clientele. I bought the ube at Paddy's Market.
White on white colouring is available at cake decorating stores by brands like Wilton.
Step 1 - Preheat oven to 160C/320F. Butter a cake tin-I used a bundt tin which was fine but it was a perhaps bit too detailed. Two 20cm/8inch plain tins are best. Cream the butter and sugar until pale and fluffy in colour. Add eggs one at a time and then add the vanilla and purple colouring. Beat until the colour is consistent throughout the mix. In a food processor, blend the ube and the oil until you get a smooth consistency. Add this into the mixture and mix until smooth.
Step 2 - Whisk the flour, baking powder and bicarb in a jug. Alternate the flour and the coconut milk until you get a smooth mixture (try not to overmix). Pour into the buttered tin. Bake for 50 minutes or until the cake bounces back when touched. If you don't bake this in a bundt tin then it will take longer, around 15-20 minutes longer or so and make sure that you check the centre. Allow to cool in the tin. Then carefully upend onto a serving plate.
Step 3 - Heat the cream until almost boiling and pour over the chocolate. Stir to melt the chocolate and add the white on white colouring. Allow the ganache to cool for 10-15 minutes (it should still be liquid but thicker to pour) and then drip it down the sides of the bundt tin. Add blackberries and petals. You can probably see that I coloured some of the chocolate purple but I don't think that really worked visually so let's just forget that m'kay? ;)